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Related papers: Nonlinear Reconstruction of the Velocity Field

200 papers

Accurate three-dimensional (3D) reconstruction of cardiac chamber motion from time-resolved medical imaging modalities is of growing interest in both the clinical and biomechanical fields. Despite recent advancement, the cardiac motion…

Medical Physics · Physics 2025-04-18 Francesco Capuano , Yue-Hin Loke , Ibrahim Yildiran , Laura Olivieri , Elias Balaras

This paper presents a novel approach for sparse 3D reconstruction by leveraging the expressive power of Neural Radiance Fields (NeRFs) and fast transfer of their features to learn accurate occupancy fields. Existing 3D reconstruction…

Computer Vision and Pattern Recognition · Computer Science 2024-10-01 Shubhendu Jena , Franck Multon , Adnane Boukhayma

We present a novel approach for the reconstruction of spectra from Euclidean correlator data that makes close contact to modern Bayesian concepts. It is based upon an axiomatically justified dimensionless prior distribution, which in the…

High Energy Physics - Lattice · Physics 2013-10-03 Yannis Burnier , Alexander Rothkopf

The Kinematic Theory of rapid movements, and its associated Sigma-Lognormal, model 2D spatiotemporal trajectories. It is constructed mainly as a temporal overlap of curves between virtual target points. Specifically, it uses an arc and a…

Computer Vision and Pattern Recognition · Computer Science 2024-01-31 Miguel A. Ferrer , Moises Diaz , Jose J. Quintana , Cristina Carmona-Duarte

We present the one-loop 2-point function of biased tracers in redshift space computed with Lagrangian perturbation theory, including a full resummation of both long-wavelength (infrared) displacements and associated velocities. The…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-14 Shi-Fan Chen , Zvonimir Vlah , Emanuele Castorina , Martin White

We consider the problem of reconstructing signals and images from periodic nonlinearities. For such problems, we design a measurement scheme that supports efficient reconstruction; moreover, our method can be adapted to extend to…

Machine Learning · Statistics 2017-10-03 Viraj Shah , Mohammadreza Soltani , Chinmay Hegde

Reconstructing high-resolution flow fields from sparse measurements is a major challenge in fluid dynamics. Existing methods often vectorize the flow by stacking different spatial directions on top of each other, hence confounding the…

Fluid Dynamics · Physics 2023-05-17 Mohammad Farazmand , Arvind K. Saibaba

Objective: To develop a fast image reconstruction method for stroke monitoring with electrical impedance tomography with image quality comparable to computationally expensive nonlinear model-based methods. Methods: A post-processing…

Image and Video Processing · Electrical Eng. & Systems 2024-12-12 J. Toivanen , V. Kolehmainen , A. Paldanius , A. Hänninen , A. Hauptmann , S. J. Hamilton

We are concerned with the inverse scattering problem of extracting the geometric structures of an unknown/inaccessible inhomogeneous medium by using the corresponding acoustic far-field measurement. Using the intrinsic geometric properties…

Analysis of PDEs · Mathematics 2017-06-15 Jingzhi Li , Xiaofei Li , Hongyu Liu

Mathematical methods of step-by-step and combined shifts are proposed for experimental data processing to reconstruct the measuring system impulse response distorted by shift-invariant blur. Proposed methods base on direct non-blind…

Signal Processing · Electrical Eng. & Systems 2019-01-24 Andrey V. Novikov-Borodin

We present a new method to calculate formation of cosmological structure in the Newtonian limit. The method is based on Lagrangian perturbation theory plus two key theoretical extensions. One advance involves identifying and fixing a…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-15 Sharvari Nadkarni-Ghosh , David F. Chernoff

Modeling complex rigid motion across large spatiotemporal spans remains an unresolved challenge in dynamic reconstruction. Existing paradigms are mainly confined to short-term, small-scale deformation and offer limited consideration for…

Computer Vision and Pattern Recognition · Computer Science 2026-01-06 Yijun Xu , Jingrui Zhang , Yuhan Chen , Dingwen Wang , Lei Yu , Chu He

We have developed a new experimental technique to measure the Lagrangian velocity of tracer particles in a turbulent flow, based on ultrasonic Doppler tracking. This method yields a direct access to the velocity of a single particule at a…

Fluid Dynamics · Physics 2009-11-07 N. Mordant , P. Metz , O. Michel , J. -F. Pinton

We introduce a new framework of numerical multiscale methods for advection-dominated problems motivated by climate sciences. Current numerical multiscale methods (MsFEM) work well on stationary elliptic problems but have difficulties when…

Computational Engineering, Finance, and Science · Computer Science 2019-05-28 Konrad Simon , Jörn Behrens

The Zeldovich approximation, 1st order Lagrangian perturbation theory, provides a good description of the clustering of matter and galaxies on large scales. The acoustic feature in the large-scale correlation function of galaxies imprinted…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Martin White

We apply an iterative reconstruction method to galaxy mocks in redshift space obtained from $N$-body simulations. Comparing the two-point correlation functions for the reconstructed density field, we find that although the performance is…

Cosmology and Nongalactic Astrophysics · Physics 2019-06-26 Ryuichiro Hada , Daniel J. Eisenstein

Here we introduce the Delaunay Density Estimator Method. Its purpose is rendering a fully volume-covering reconstruction of a density field from a set of discrete data points sampling this field. Reconstructing density or intensity fields…

Astrophysics · Physics 2007-05-23 W. E. Schaap , R. van de Weygaert

We study the inverse problem of reconstructing an incompressible velocity field $\boldsymbol{v}$ from observations of the induced magnetic field $\boldsymbol{b}$. In the presence of a strong, constant background field $\mathbf{F}$, the…

Analysis of PDEs · Mathematics 2026-02-26 Yacine Mokhtari , Christina Frederick , Yunan Yang , Bjorn Engquist

In this paper, we develop a novel phase retrieval approach to reconstruct x-ray differential phase shift induced by an object. A primary advantage of our approach is a higher-order accuracy over that with the conventional linear…

Medical Physics · Physics 2010-03-18 Wenxiang Cong , Ge Wang

A lot of predictions for the statistical properties of the cosmic velocity field at large-scale have been obtained recently using perturbation theory. In this contribution I report the outcomes of a set of numerical tests that aim to check…

Astrophysics · Physics 2007-05-23 Francis Bernardeau